Patrick had 2,000 ducks and chickens on his farm. He had 3 times as many chickens as ducks. After selling some chickens, he now has twice as many ducks as chickens. How many chickens did he sell?
Let Patrick had 'x' number of Ducks.
Since he had 3 times as many chickens as ducks.
∴ Number of chickens Patrick had = 3x
Since he had a total of 2000 Ducks and chickens,
∴ 3x + x = 2000
⇒ 4x = 2000
⇒ x = 500
∴ Number of Ducks Patrick had = 500
And number of Chickens Patrick had = 3x = 3 × 500 = 1500
Now he sells some chicken and after selling he now has twice as many ducks as chickens.
Let he sells 'y' number of chickens,
∴ Number of chickens left = 1500 - y
And the number of Ducks = 500
he now has twice as many ducks as chickens.
∴ 2 × (1500 - y) = 500
⇒ 3000 - 2y = 500
⇒ 2y = 2500
⇒ y = 1250
this means that he sold 1250 chickens.
ANSWER :
Number of chickens Patrick sold = 1250